Implement sdcard resizing.

rootfs-overlay/arm/etc/part-expand.sh

@@ -0,0 +1,24 @@
+#!/bin/sh
+# This should resize the sdcard to its full capacity.
+
+[ -f /etc/part-expanded ] && exit 0
+
+cat <<EOF | fdisk /dev/mmcblk0
+d
+2
+n
+p
+2
+
+
+Y
+w
+EOF
+
+partprobe
+
+mount /dev/mmcblk0p2 /mnt
+btrfs fi re max /mnt
+umount /mnt
+
+echo yes > /etc/part-expanded

rootfs-overlay/common/etc/rc.local

@@ -2,6 +2,7 @@
 # rc.local for base images
 
 [ -f /etc/ssh/ssh_host_rsa_key.pub ] || ssh-keygen -A
+[ -f /etc/part-expand.sh ] || /etc/part-expand.sh
 
 netdata